Energy storage is accomplished by devices and/or physical media configured to receive and to store energy, and to provide the stored energy that is to be consumed or used at a later time (on demand) for useful operations as may be required. A device configured to store energy is called an energy-accumulation apparatus.
A renewable-energy system (such as a wind turbine and/or a solar panel) is configured to convert energy received from a renewable-energy source (wind and/or solar) into electricity, which may be classified as intermittent electric power. Wherever intermittent power sources are connected to (deployed in) an electrical grid (or grid), energy storage becomes an option to improve reliable supply of energy.
A technique called renewable-energy time shift is a method that includes the use of energy storage to mitigate rapid output changes from the generation of electricity based upon the variability of renewable-energy sources, due to: (A) wind speed variability affecting wind generation, and/or (B) shading of solar generation due to cloud cover. Generated electricity is stored in the energy-accumulation apparatus (such as a battery) when the demand is relatively lower, and when renewable sources are active; later, when the demand for electricity increases, the energy stored in the energy-accumulation device is used for the purpose of generating electricity to be applied to the electric grid.
In view of the foregoing, many technical problems associated with the storage of energy (such as the storage of energy derived from renewable-energy sources) continue to challenge the renewable-energy industry faced with the increased demand for affordable electric energy.